They say if you invest in bricks and mortar your money is as safe as houses.

Which is true for the owner of this hole in the ground who stands to make about £90,000 profit on his flat in just over a year.

Built in a former bank vault with six-inch metal-plated walls, this two-bedroom flat in Church Road, Hove is thought to be the first in Brighton and Hove to be built entirely underground.

Experts believe it could be the most secure home in Britain.

The flat first went on the market with Mishon Mackay in January 2006 for £279,000. Now it is back on the market with King and Chasemore at £365,000.

Gary Parsons, King and Chasemore Hove branch manager, said: "It came on the market about four weeks ago and it is beautiful inside.

"The owner bought it a year ago and has decided he wants to invest his money. It is really a bachelor pad at the moment but would be suitable for lots of different people.

"We have had quite a bit of interest from young professional couples, people who commute to work and people who want to use the property as a holiday let."

The bank vault, which belonged to the Lloyds TSB bank which used to based be above, was bought in 2001 by Charter House Consultancy. They teamed up with Brighton-based architects Peter Overill Associates to design the flat.

A safe and a lift had to be removed to clear the space and all the walls had to be knocked down and rebuilt.

The bank vault is the latest in a line of new homes tackling the growing housing problem in Brighton and Hove, which is wedged between the Downs and the sea.

Mr Parsons said: "The bathroom is a particularly nice feature and it has a television screen set into the wall.

"The shower cubicle is all glass and even though the kitchen, lounge and dining room are all open plan they still feel separate from one another.

"People think that because it is a bank vault it is going to be dark and dingy but really it is a lower ground floor flat and a lot of light gets in.

"Both the bedrooms have French doors which open out into a courtyard in Holland Road. I think it is a unique property in the city.

"The walls are so thick which means the sound-proofing is fantastic and it is probably one of the most secure homes in Brighton and Hove."

The Argus reported on Thursday about a former police box on the corner of Stanford Avenue and Ditchling Road, near Fiveways in Brighton, which is to go under the hammer.

The guide price for the 10m (33ft) by 13.7m (45ft) building is between £70,000 and £90,000 but is is expected to go for twice as much.

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